I was of two minds when I heard Steven Spielberg and Tom Cruise were doing an adaptation of H.G. Wells's "War of the Worlds" set in the present day. The first was excited, because there aren't many directors around as good at science fiction as Spielberg is, but the second was kind of cranky. Orson Welles and George Pal had each updated the story, and doing it as a period piece might have been an interesting, different angle. Or, why not use more modern source material (Niven & Pournelle's "Footfall" has been begging to be adapted for nearly two decades now)? But "War of the Worlds" is what they did, and they did it very well indeed, hitting only one or two false notes along the way.

The script by Josh Friedman and David Koepp tackles the story not from the perspective of those fighting the war, but instead of a family caught in its path. Ray Ferrier (Cruise) has custody of his kids for the weekend, but it's contentious: Teenage son Robbie (Justin Chatwin) is openly hostile, while ten-year-old daughter Rachel (Dakota Fanning) is developing tastes and attitudes that don't quite mesh with Ray's working-class sensibilities. Everything's just starting to feel good and uncomfortable when a freakish lightning storm hits. When Ray goes to investigate, he and a crowd of onlookers find that the bolts have blasted a hole in the ground. A gigantic three-legged machine climbs out and starts vaporizing people, few of whom act as decisively - and sensibly - as Ray in running away. They decide to head from New York to Boston, because that's where the kids' mother (Miranda Otto) is, and, well, you've got to have a destination, even if it's really no safer than where you're leaving.

The filmmakers and cast tap into the basic fear of the unknown here, which is what drives the tension. There is some narration in the beginning that describes the invaders' motivation in the very vaguest of terms (Morgan Freeman reading the beginning of H.G. Wells's novel with some dates changed), and a similar passage at the end, but as the Ferriers make their way cross-country, there's no explanations to be had as to why now, why the invaders sometimes disintegrate people indiscriminately and sometimes take them up into walkers. Or why the walkers appear to have been buried millennia ago only to be unearthed now. Even if they weren't alien beings doing alien things for alien reasons, the information would be irrelevant - the important information is that they're killing people and no sane man wants to be near them. If you like the nuts and bolts of science fiction, the speculation on how incredible things could be, you won't find it here. This is the Biblical Exodus with laser guns grafted onto it, much like many sci-fi films are standard action movies with laser guns.

This puts the onus of carrying the movie mostly on the performances, and they handle it pretty well. Tom Cruise is often underrated as an actor because a non-trivial portion of his success can be attributed to his good looks. He is, perhaps, incongruously handsome and unweathered for a Port Authority crane operator, but he still makes the role work; he doesn't come across as a movie star wearing a thin disguise of non-designer clothing: Ray Ferrier is a guy who has carved out what strikes him as a pretty nice, if not perfect, life, and it confuses and sometimes frustrates him that his family doesn't find it as comfortable or satisfying as he does. He's not book-smart, but he's good at sizing up a situation and coming up with a practical response - even when that action must be rather cold-blooded.

Ray is our viewpoint character, in every scene to an extent that would indicate a first-person narrative in print, and the other characters make their impression by how they play against him. Miranda Otto's part is brief, but she and Cruise nail the divorced parent dynamic of truly wanting to get along but not being able to live up to their good intentions. The divorce is the main factor in how Cruise and the younger actors interact, too: Chatwin's Robbie is at an age where he tends to bounce between knowing it all and not knowing anything; the audience can easily believe in their contentious relationship. Fanning, meanwhile, plays Rachel as not really having a lot of use for the father she doesn't see very often; it's Robbie she turns to when she's scared and she has more of an affinity for her less working-class stepdad. The pair never really connect, and in fact Rachel doesn't really understand what her father goes through to keep her safe from harm and images that would haunt her nightmares, but that's the point. I like that she dials back the child-actor precociousness as the film goes on; she doesn't seem like a little adult, even if her character is trying to come off that way in the first act. A bit less solid is Tim Robbins as Harlan Oglivy, a fellow survivor whom the Ferriers encounter midway through the movie. He's been driven mad by what he's seen, and it's tough to convey that without having seen him before the invasion; how are we supposed to know he hasn't always been like this?

While War of the Worlds is about the characters more than the spectacle, that doesn't mean Spielberg stints on the latter. The tripods are unmistakably cool, combining a nineteenth-century industrial look with grotesquely pliant, almost biological influences. I like how the death rays disintegrate people in a literal-seeming sense, leaving piles of dust that used to be human beings or cars or buildings around; it's in some ways more horrifying than just having the victims disappear or be burned. There's also one shot that dropped my jaw in a "how did they do that?" way, as the Ferriers flee New York in a stolen car, and Janusz Kaminski's camera pulls in and out in what looks like a continuous shot that includes both the actors talking and the road around them being high-speed chaos. I know CGI had to be involved, but I'll be damned if I can tell whether the car was composited into a car chase or whether stunt driving was added to some fancy camerawork. Impressive either way.

The movie's a single tick less than perfect, but it's the kind of single tick that creates a disproportionately bad impression because it's near the end. Not the resolution to the invasion - after all, without that, it wouldn't be "War of the Worlds", but there's parts that not all of the cast seems to have earned. Still, that's a couple minutes that shouldn't nullify how great the previous two hours are.